Vortex inhibitor with sacrificial rod

ABSTRACT

An improved vortex inhibitor for separating slag from molten metal during the discharge of molten metal through a nozzle includes a uniform castable refractory body with a generally tapering shape, a hollow chamber within the body and an elongated sacrificial member. The hollow chamber receives the sacrificial member or a mount for the sacrificial member. The refractory body and the sacrificial member combination in molten metal has a specific gravity less than the specific gravity of molten metal and is positioned narrow end downward when supported in molten metal. The hollow chamber can fill with molten metal to form a core that aids in orienting the body in a narrow end downward position. The sacrificial member align the with the area in which the vortex forms and minimizes interference with the flow through the discharge nozzle. The body preferably includes swirl obstructing surfaces.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the priority of U.S. patent applicationSer. No. 09/761,465, filed on Jan. 16, 2001, published on Jul. 18, 2002as US 2002/0093128, issued on as U.S. Pat. No. ______, and entitled“Vortex Inhibitor With Sacrificial Rod”.

FIELD OF THE INVENTION

[0002] The present invention relates to a device for separating slagfrom molten metal as the molten metal is transferred from a receptacle.

BACKGROUND ART

[0003] In metal making processes, a layer of slag comprising metalimpurities forms atop the surface of molten metal held within a metalreceptacle such as a furnace, tundish or ladle. As the molten metal isdrained from the receptacle, the flow of molten metal through thedischarge induces a swirl above the discharge nozzle. At a criticallevel, the energy of the swirl creates a vortex, whereby the slag layeris sucked into the nozzle, thus contaminating the pour. Separation ofthe slag and molten metal enhances the quality of the discharge.

[0004] Several devices have been known to inhibit the introduction ofthe slag into the nozzle via the sucking effect of the nozzle. Many ofthe previously known devices for restricting slag flow through thedischarge nozzle were in the form of a refractory body and extending rodcombination. For example, the abstract of German Disclosure DE 19821981A1 to Stilkerieg discloses a slag retainer consisting of a closure bodyand a finned guide bar. The fin elements consist of a refractorymaterial, preferably a refractory concrete. The closure body also has abar protruding perpendicularly upwards from the base of the closurebody. This bar is attachable to an arm which positions the slag retainerover the tapping channel. Although suitable for its intended purpose,the fin elements are expensive to fabricate. Therefore, the use of afinned guide bar substantially increases the costs of metal making.Moreover, the extending rod enters the tap hole and stifles the flow ofmolten metal through the nozzle during the pouring process.Consequently, metal pouring operation using this refractory body andextending rod combination extends processing time, and thus increasesproduction costs.

[0005] U.S. Pat. No. 4,799,650 to LaBate discloses a slag retainerconsisting of a tapered, circular refractory closure having a tapered,hexahedron-shaped, refractory extension. The circular closure is sizedsufficiently to close the tap hole. A metal rod is passed through thecenter of the circular closure and extends downwardly into the elongatedhexahedron shaped extension to join the circular closure and thehexahedron-shaped extension. The hexahedron extension prematurelythrottles the flow of molten metal through the discharge nozzle.Consequently, a significant amount of usable molten metal remains in thereceptacle after the pour is stopped, substantially decreasing the totalmolten metal released per pour, and thus increasing operation costs.

[0006] U.S. Pat. No. 4,494,734 to LaBate et al. discloses a slagretainer with a modified cone-shaped refractory body and a rod. The rodextends below the center of the body and is covered with refractorysleeves. The upper extension contains a swivel mechanism which is usedto engage a mechanical device that positions the slag retaining deviceover the tap hole. The patent also covers a method of minimizing slagcarryover by dropping a body having a plurality of generally irregularfaces and a guide means within a restricted area, draining a furnace,monitoring the stream for flaring, and shutting off flow through the taphole. Unfortunately, continuous intrusion of the guide means extends thetime for discharging metal and may encourage operators to prematurelyterminate the flow of the molten metal. Additionally, the process ofconstructing and affixing refractory sleeves to the downward extensionsignificantly increases the cost of manufacturing the slag retainer.

[0007] U.S. Pat. No. 4,709,903 to LaBate discloses a slag retainerconsisting of a barrel shaped refractory body and a rod. The rod extendsvertically through the barrel shaped body and upwardly and downwardlythereof. The upward extension is engaged to a mechanical device used toposition the slag retaining device over the tap hole. The downwardextension is covered with refractory sleeves. However, the downwardextension enters the tap hole and continues to prematurely restrain theflow of molten metal through the discharge nozzle. Consequently, aspreviously discussed, the problem of premature termination of the pourresults. The problems of shaping and assembling previously discussed arealso encountered.

[0008] U.S. Pat. No. 4,610,436 to LaBate, II et al. discloses a slagretaining closure having a tapered body and an elongated guide meansconsisting of an elongated guide member and tip portion depending fromthe closure. A tip portion of the guide member having a recess or acavity accelerates and aligns the guide member with the tap hole. Theportion of the guide member extending below the tapered end of theclosure is coated with refractory sleeves. As with the otherdisclosures, operation costs are increased due to premature throttlingand pour termination. Moreover, the use of the intricate elongated guidemeans substantially increases manufacturing complexity and has beendisfavored.

[0009] The previously known refractory body and extending rodcombinations suffer from additional disadvantages. These combinationsrequire pre-assembly. The resulting unit requires special packaging toensure that the extending rod does not break off during delivery.Additionally, the cumbersome shape of the body and rod combinationdecreases the amount of units that can be shipped in any given space.Moreover, the elongated rods of existing devices may strike the wall ofthe receptacle instead of entering their intended position in the taphole. Since the vortex forms above the tap hole, incorrectly positioneddevices have little or no effect on inhibiting the vortex. The shippingand operational problems contribute to a lack of industry acceptance ofvortex inhibitors with a body and rod combination.

SUMMARY OF THE INVENTION

[0010] The present invention overcomes the abovementioned disadvantagesby providing a vortex inhibitor using a refractory body with a hollowchamber adapted to receive a sacrificial member. The vortex inhibitorhas a specific gravity less than the specific gravity of molten metaland is self-orienting in a narrow end downward position in a moltenmetal bath. The sacrificial member does not inhibit the flow of themolten metal since it can dissipate shortly after introduction into themetal bath. Additionally, even if the sacrificial rod strikes the wallof the receptacle, the rod can dissipate shortly after introduction intothe receptacle, thus freeing the body to relocate to the area in whichthe vortex forms. Furthermore, the sacrificial member may be constructedof inexpensive metal rod, bar, pole, or other types of elongated memberssuch as tubes, rather than the intricate and expensive guide systems ofthe prior art.

[0011] In general, the vortex inhibitor of the present inventioncomprises a tapering, castable refractory body, a hollow chamberpositioned longitudinally to the axis of tapering of the body, and anelongated sacrificial member carried by the hollow chamber. It is to beunderstood that the term castable refractory is a uniform mixture, butuniform does not require complete homogeneity of material and includesthe intermixture of shot, steel fiber or other materials which may beconsistently mixed with a castable refractory material to adjust thespecific gravity of the body. In any event, the specific gravity of theuniform mixture is selected so that the body and sacrificial membercombination is buoyantly supported at the interface of the slag layerand the molten metal layer. Moreover, the vortex inhibitor of thepresent invention does not require assembly before shipping, thusreducing the difficulty and cost associated with shipping previouslyknown bodies with guides.

[0012] The body has a generally tapering shape along a longitudinal axisfrom a base toward a narrow end. The term generally tapering means thatthe body generally conforms with the shape of the vortex formed by theswirling molten metal above the discharge nozzle. The cross-sectionalarea of the base is greater than that of the narrow end. As used herein,the term narrow end is to be understood as not defining any particularshape, and may include a pointed end, a rounded end or a flat surface.The base can be formed from a simple or complex polygon, or a rounded orcircular figure. Complex polygonal bases may include flats, recesses ornotches. These features may extend lengthwise along the body. The taperis preferably consistent along the length of the body. The refractorybody is preferably constructed by creating a mold of the generallytapering shape.

[0013] The hollow chamber is positioned longitudinally to thelongitudinal axis of the body and extends within the body. The mold usedto construct the refractory body has an insert, preferably in the formof a shaft which forms the hollow chamber during the curing process.Depending on the application, the shaft may be separated from therefractory body or retained within the refractory body once the moldedmixture cures. If the shaft is separated from the refractory body, theresulting empty hollow chamber snugly receives the elongated sacrificialmember. If the shaft is retained after construction, the sacrificialmember is attached to an end of the shaft. In either event, whenintroduced into the molten metal receptacle, the hollow chamber may fillwith molten metal that forms a core within the refractory body. Themetal core helps orient the refractory body in a narrow end downwardposition.

[0014] The sacrificial elongated member may be constructed of hollow orsolid metal and can be coated with a refractory material. If theelongated member is hollow, then the hollow can be filled withrefractory material, as well. When the vortex inhibitor is placed in amolten metal receptacle, the sacrificial member can align the vortexinhibitor with the area in which the vortex would be likely to form. Asthe pouring process continues, the sacrificial member can dissolve intothe molten metal bath, and thereby does not interfere with the flow ofmolten metal through the discharge nozzle.

[0015] Thus, the present invention provides a vortex inhibitor having arefractory body, a hollow chamber within the refractory body and asacrificial member. These features help orient the refractory body sothat its narrow end extends downwardly toward the discharge nozzle of amolten metal receptacle while not reducing the flow of molten metalthrough the discharge nozzle. When inserted into a molten metal bath,the resulting body and sacrificial member combination has a specificgravity less than the specific gravity of the molten metal. Preferably,the refractory body maintains a center of gravity closer to the narrowend than a center of buoyant support even when the rod has dissolved.Additionally, since the elongated member is sacrificial, it can dissolvebefore creating a throttling effect upon the discharge flow.

[0016] As a result, the present invention permits substantially completedrainage of the furnace with minimal intermixture of the slag and moltenmetal layers. Moreover, it will be understood that the present inventioncan also be used for other molten metal receptacles, such as ladles andtundishes, in which separation of the slag from molten metal must bemaintained while the metal is discharged from the receptacle.

BRIEF DESCRIPTION OF DRAWINGS

[0017] The present invention will be more clearly understood byreference to the following detailed description of the embodiments ofthe present invention when read in conjunction with the accompanyingdrawings in which like reference characters refer to like partsthroughout the views and in which:

[0018]FIG. 1 is an elevational view of a molten metal receptaclecontaining a vortex inhibitor constructed in accordance with the presentinvention;

[0019]FIG. 2 is a perspective view of the vortex inhibitor shown in FIG.1;

[0020]FIG. 3 is a sectional view taken substantially along the line 3-3in FIG. 2;

[0021]FIG. 4 is a sectional view of an embodiment of a vortex inhibitorconstructed in accordance with the present invention;

[0022]FIG. 5 is a sectional view of a further embodiment of a vortexinhibitor constructed in accordance with the present invention;

[0023]FIG. 6 is a sectional view of yet another embodiment of a vortexinhibitor constructed in accordance with the present invention;

[0024]FIG. 7 is a sectional view of a further embodiment of a vortexinhibitor constructed in accordance with the present invention.

[0025]FIG. 8 is a top plan view of a modified refractory bodyconstructed in accordance with the present invention;

[0026]FIG. 9 is a sectional view taken substantially along the line 9-9in FIG. 8;

[0027]FIG. 10 is a top plan view of another modified refractory bodyconstructed in accordance with the present invention;

[0028]FIG. 11 is a sectional view taken substantially along the line11-11 in FIG. 10;

[0029]FIG. 12 is a top plan view of a further modification of arefractory body constructed in accordance with the present invention;

[0030]FIG. 13 is a sectional view taken substantially along the line13-13 in FIG. 12;

[0031]FIG. 14 is a top plan view of another modified refractory bodyconstructed in accordance with the present invention;

[0032]FIG. 15 is a sectional view taken substantially along the line15-15 in FIG. 14;

[0033]FIG. 16 is a top plan view of yet another modified refractory bodyconstructed in accordance with the present invention; and

[0034]FIG. 17 is a perspective view of the body shown in FIG. 16.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

[0035] Referring first to FIG. 1, a molten metal receptacle 10 is shownhaving a bottom wall 12 with a discharge nozzle 14 and nozzle opening16. The molten metal receptacle 10 can be a furnace, ladle, reservoir,tundish or other receptacle from which molten metal is dischargedthrough a nozzle 14. Regardless of the type of receptacle, thereceptacle 10 is shown containing a layer of molten metal 18. A layer ofslag 20, having a specific gravity less than the specific gravity of themolten metal 18, rests on top of the layer of molten metal 18. A vortexinhibitor 22 according to the present invention is shown supported atthe interface of the slag layer 20 and the molten metal layer 18 withinthe receptacle 10.

[0036] Referring now to FIGS. 2 and 3, the vortex inhibitor 22 comprisesa body 24 having a base 26 and narrow end 28, a hollow chamber 30 and anelongated sacrificial member 32. As depicted by the upward arrows inFIGS. 2 and 3, the sacrificial member 32 slides into the hollow chamber30 to form an integral vortex inhibitor. Alternatively, the refractorybody 24 can be molded around the sacrificial member 32. The sacrificialmember 32 may be modified with crimps 25 or protrusions 27, which mountthe sacrificial member 32 in the hollow chamber 30 once the refractorybody 24 cures.

[0037] The outermost points of the base intersect a circle 33circumscribed about the base. The diameter of the circle 33 is largerthan the diameter of the nozzle opening 16 so that only a portion of thebody may become lodged within the nozzle. Due to the harsh environmentalconditions within the furnace, the diameter of the circle may besubstantially larger than the diameter of the nozzle opening 16 so thaterosion of the body does not reduce the maximum diameter of theoutermost points of the base to less than the diameter of the nozzleopening.

[0038] The body 24 generally tapers downwardly from the base 26 towardsthe narrow end 28. The resulting generally tapering shape issubstantially regular so that cross-sectional shapes sliced downwardlyfrom and perpendicularly to the base 26 towards the narrow end 28 aresubstantially congruent. However, some variation in the cross-sectionalshapes can be accommodated.

[0039] When the body 24 and the sacrificial member 32 combination issupported at the interface of the slag layer 20 and the molten metallayer 18, the combination is self-orienting in a narrow end downwardposition. In the present embodiment, this orientation can be aided bythe hollow chamber 30 and the sacrificial member 32. Specifically, afterthe vortex inhibitor 22 is dropped into the molten metal receptacle 10,the hollow chamber 30 can fill with molten metal that forms a core. Thecore acts to stabilize the position of the vortex inhibitor 22 in themolten metal so that the narrow end 28 points downwardly when the vortexinhibitor floats at the slag-metal interface. Additionally, thesacrificial member 32 may enter the discharge nozzle 14 for a limitedtime before dissipating. During this initial period before dissipation,the sacrificial member steadies the vortex inhibitor 22 in a narrow end28 downward position. Moreover, the sacrificial member 32 can initiallyalign the vortex inhibitor 22 with the area in which the vortex would belikely to form. Even if the sacrificial rod dissolves, the refractorybody maintains a center of gravity 29 closer to the narrow end than acenter of buoyant support 31.

[0040] The sacrificial member 32 is preferably a metal pipe, rod or bar.The length and width of the sacrificial member can be varied greatly aslong as the resulting vortex inhibitor construction has a specificgravity less than the specific gravity of the molten metal and isself-orienting in a narrow end downward position when supported inmolten metal. A refractory coating 34 is optionally attached to thesurface of the sacrificial member 32. If the sacrificial member ishollow, a refractory coating or core 35 may be included within thehollow sacrificial member. Depending on the operating conditions of themolten metal receptacle, an interior or exterior refractory coating mayprolong the life of the sacrificial rod 32. The sacrificial nature ofthe elongated member does not impinge on the flow of molten metalthrough the discharge nozzle 14.

[0041] Referring now to FIG. 4, the vortex inhibitor 36 is shown withmodifications 37 to the hollow chamber 30 and modifications of thesystem of attaching the elongated sacrificial member 38 to therefractory body 40. In the embodiment shown, a hollow shaft 42 is snuglypositioned in the hollow chamber 30, for example, by using the sleeve asthe mold insert during pouring of the refractory material. The shaft 42extends beyond the base 44 of the vortex inhibitor 36. The exposedportion 46 of the hollow shaft 42 contains a notch 45 adaptable forreceiving a locating arm (not shown). The locating arm is responsiblefor positioning the vortex inhibitor 36 over the area in which thevortex would be likely to form and selectively dropping the vortexinhibitor into the molten metal receptacle. In the embodiment shown, thesacrificial member 38 is attached to the hollow shaft 42 by the use of anipple 48, which contains external screw threads 50 on both ends. Thenipple 48 mates with the hollow shaft 42, which has internal screwthreads 52, and mates with an end of the sacrificial member 38, whichcontains internal screw threads 54.

[0042] Referring now to FIG. 5, the vortex inhibitor 56 is shown with afurther modification to the system of attaching the sacrificial member58 to the hollow shaft 60. The sacrificial member 58 connects to thehollow shaft 60 through screw threading although other connectors mayalso be used. External screw threads 62 contained on an end of thesacrificial elongated member mates with internal screw threads 64 on thehollow shaft 60. As with the embodiment shown in FIG. 4, the hollowshaft 60 has an exposed portion 66 which may contain a notch 68 forreceiving a locating arm (not shown).

[0043] Referring now to FIG. 6, the vortex inhibitor 70 is shown withmodifications 72 to the hollow chamber 30 and modifications as shown at74 and 76 to the system of attaching the elongated sacrificial member tothe refractory body. In the embodiment shown, a solid shaft 78 is snuglypositioned in the hollow chamber 30 and extends beyond the base 80 andnarrow end 82 of the vortex inhibitor 70. The portion 84 extendingbeyond the base 82 of solid shaft 78 contains a bore 86 adaptable forreceiving a locating arm (not shown). The locating arm is responsiblefor positioning the vortex inhibitor 70 over the area in which thevortex would be likely to form and selectively dropping the vortexinhibitor into the molten metal receptacle. In the embodiment shown, theportion 88 extending beyond the narrow end 82 of solid shaft 78 containsexternal screw threads 91. Likewise, an end of sacrificial member 74contains external screw threads 90, although other connectors may beused. A coupling 92 mates the solid shaft 78, which has external screwthreads 91, with the end of the sacrificial member 74 containingexternal screw threads 90, thus forming an integral refractory body andsacrificial member combination.

[0044] Referring now to FIG. 7, the vortex inhibitor 94 is shown withfurther modifications 96 to the hollow chamber 30 and modifications 97to the system of attaching the elongated sacrificial member to therefractory body. In the embodiment shown, a solid shaft 98 is snuglypositioned in the hollow chamber 30 and extends both beyond the base 100and the narrow end 102 of the vortex inhibitor 94. Alternatively, thesolid shaft 98 may only extend beyond the narrow end 102 of the vortexinhibitor 94, thus forming a bolt 101. The portion 104 extending beyondthe base 100 of solid shaft 98 contains a bore 106 adaptable forreceiving a locating arm (not shown). If the bolt 101 is utilized, thebase 100 can be fitted with a hook (not shown) adaptable for receivingthe locating arm (not shown). The locating arm is responsible forpositioning the vortex inhibitor 94 over the area in which the vortexwould be likely to form and selectively dropping the vortex inhibitorinto the molten metal receptacle.

[0045] In the embodiment shown, the portion 108 of solid shaft 98 orbolt 101 extending beyond the narrow end 102 is of suitable diameter tosnugly receive the hollow sacrificial member 97. This snug fit may beachieved by varying the diameter of the extending portion 108 orcreating gripping surface features, for example protrusions 109, on thesurface of the extending portion 108. However the snug fit isaccomplished, the result is an integral refractory body and sacrificialrod combination.

[0046] Regardless of the method by which the sacrificial member isjoined with the shaft, the specific gravity of the vortex inhibitorsupports it at the interface of the slag layer 20 and the molten metal18. Further, regardless of the joining method, the outside surface ofthe sacrificial member may be coated with refractory material.Additionally, the inside surface of a hollow sacrificial member may becoated with refractory material.

[0047] Referring now to FIGS. 8 and 9, the vortex inhibitor is shownwith a modified body 110 having an octagonal base 112 and flat sides114. As with the embodiment shown in FIG. 2, the vertices 116 of theoctagonal base intersect a circle 118 circumscribed about the base andhaving a diameter dimensioned to exceed the diameter of the nozzleopening 14. In addition, the body 110 tapers downwardly toward a narrowend 120 in a substantially regular manner.

[0048]FIGS. 10 and 11 show a further modification of a generallytapering body 122 of vortex inhibitor. As shown in the drawings, a body122 has a substantially circular base 124. However, unlike the flatsides of the bodies 24 and 110 shown in FIGS. 2 and 8 respectively,surfaces for enhancing fluid contact that inhibiting the vortex areformed by recesses 126 extending along the sides of the refractory body122.

[0049] The embodiment as shown in FIGS. 12 and 13 is similar to FIG. 10but vortex inhibiting is enhanced by projections extending outwardlyfrom the periphery of a substantially conical body 128. Like therecesses 126 shown in the body 122, a projection 130 can be tapered fromthe base 134 toward the narrow end 132, preferably tapering.Alternatively, like the recesses 126 in the body 122, the projections130 extends from the base 134 to the narrow end 132 as shown in phantomline at 136. Moreover, while the recesses 126 or the projections 130 aremost effective when extending along the entire length from the base tothe narrow end, it may be understood that such projections and recessesmay be truncated short of the entire length of the body as shown inphantom line at 138. Variations in the width and the depth of theprojections or recesses are also possible, as indicated by the constantheight projections illustrated in phantom line at 140 in FIG. 13. Inaddition, a combination of vortex inhibiting surfaces, for example, acombination of recesses and projections, can also be employed as desiredwithout departing from the scope of the present invention. As a furtherexample, flat sided recesses 142 are shown in phantom line at 142 inFIG. 12.

[0050] While the previously described embodiments have a base with asimple geometrical shape, it is also to be understood that complexgeometrical shapes can also be employed in producing the vortexinhibitor according to the present invention. FIGS. 14 and 15 disclose arefractory body 144 having a complex polygonal base 146. In particular,the base 146 combines a plurality of simple polygonal shapes emanatingoutwardly from the center of the body 144. The intersection of therectangular polygons 148 form planar surfaces 150 and 152 whichintersect in a “V” and inhibit vortex action, while the depth of theV-shaped recesses control the throttling effect once the body penetratesthe nozzle opening 14.

[0051] As shown in FIGS. 16 and 17, a substantially spherical body 154can be modified to include vortex inhibiting surfaces by cutting regularrecesses in the spherical structure. The modification shown in FIGS. 16and 17 is formed by truncating the sphere at the intersections of aregular tetrahedron and the sphere, although other truncations orprotrusions may be added. The flat sides 156 taper downwardly toward theapex 28.

[0052] All of the previously described modifications to the shape of therefractory body have common characteristics. All of the shapes provideinertia against the swirling motion of molten metal above the dischargenozzle 14. Additionally, the shape of the refractory body inhibits theformation of vortex suction, a phenomena responsible for drawing slagimpurities into the molten metal poured through the nozzle.Nevertheless, the sacrificial rod adds additional control and stabilitywithout inhibiting the discharge of molten metal. It is also understoodthat any of the previously described refractory body shapes may becombined with any of the previously described mounts or methods ofjoining the sacrificial member with the refractory body in order to forman integral refractory body and sacrificial rod combination.

[0053] Having thus described the present invention, many modificationsthereto will become apparent to those skilled in the art to which itpertains without departing from the scope and spirit of the presentinvention as defined in the appended claims.

What is claimed is:
 1. A vortex inhibitor for molten metal pouring froma discharge nozzle comprising: a uniform castable refractory body havinga generally tapering shape along a longitudinal axis from a base towarda narrow end and a hollow chamber positioned longitudinally to the bodyextending within the body; and an elongated sacrificial memberconstructed to dissolve before substantially obstructing the dischargenozzle and retained by the hollow chamber to form an integral body;whereby the integral body combining the refractory body and thesacrificial member has a specific gravity of about 2.3 to about 7.0, andis self-orienting in a narrow end downward position when supported inmolten metal.
 2. The vortex inhibitor of claim 1 wherein protrusionsextending outwardly from the sacrificial member mount in the hollowchamber to form an integral body.
 3. The vortex inhibitor of claim 1wherein crimps extending outwardly from the sacrificial member mount inthe hollow chamber to form an integral body.
 4. The vortex inhibitor ofclaim 1 wherein molten metal is disposed within the hollow chamber uponintroduction into the metal receptacle.
 5. The vortex inhibitor of claim1 wherein the sacrificial member is hollow.
 6. The vortex inhibitor ofclaim 1 wherein the sacrificial member is a solid bar.
 7. The vortexinhibitor of claim 1 wherein an exposed surface of the sacrificialmember is coated with a refractory material having a refractory coatingthickness.
 8. The vortex inhibitor of claim 7 wherein the refractorycoating thickness is less than about 9 millimeters.
 9. The vortexinhibitor of claim 3 wherein the sacrificial member is filled with arefractory material.
 10. The vortex inhibitor of claim 1 wherein thebody includes a complex polygonal base.
 11. The vortex inhibitor ofclaim 1 wherein the base is hexagonal.
 12. The vortex inhibitor of claim1 wherein the base is octagonal.
 13. The vortex inhibitor of claim 1wherein the specific gravity of the elongated sacrificial member is inthe range of about 3.5 to 7.9.
 14. A vortex inhibitor for molten metalpouring from a discharge nozzle comprising: a uniform castablerefractory body having a generally tapering shape along a longitudinalaxis from a base toward a narrow end and a shaft positionedlongitudinally to the body extending within the body; and an elongatedsacrificial member constructed to dissolve before substantiallyobstructing the discharge nozzle and retained by the shaft to form anintegral body; whereby the integral body combining the refractory bodyand the sacrificial member has a specific gravity of about 2.3 to about7.0, and is self-orienting in a narrow end downward position whensupported in molten metal.
 15. The vortex inhibitor of claim 14 whereinthe shaft is hollow.
 16. The vortex inhibitor of claim 14 wherein theshaft is solid.
 17. The vortex inhibitor of claim 15 wherein thesacrificial member contains external screw threads.
 18. The vortexinhibitor of claim 16 wherein the sacrificial member contains externalscrew threads.
 19. The vortex inhibitor of claim 17 wherein an end ofthe shaft contains internal screw threads, wherein the external screwthreads on the sacrificial member and internal screw threads arematable.
 20. The vortex inhibitor of claim 15 wherein the sacrificialmember contains internal screw threads and an end of the shaft containsinternal screw threads.
 21. The vortex inhibitor of claim 20 furthercomprising a nipple with external screw threads at each end, wherein thenipple mates the sacrificial member with the shaft.
 22. The vortexinhibitor of claim 18 wherein an end of the shaft contains externalscrew threads.
 23. The vortex inhibitor of claim 22 having a couplingcontaining internal screw threads, wherein the coupling mates thesacrificial member with the shaft, whereby the body and the sacrificialmember combination form an integral vortex inhibitor.
 24. The vortexinhibitor of claim 14 wherein the sacrificial member is hollow.
 25. Thevortex inhibitor of claim 24 wherein the sacrificial member ispositioned snugly over the shaft.
 26. The vortex inhibitor of claim 14wherein the shaft extends partially within the body.
 27. The vortexinhibitor of claim 14 wherein the specific gravity of the elongatedsacrificial member is in the range of about 3.5 to about 7.9.